Flush relief valve having floatable sleeve member

ABSTRACT

Apparatus for delaying initiation of a successive flush cycle in a plumbing system utilizing a diaphragm flush valve having a relief valve assembly provided with a buoyant relief valve sleeve member that can rise in water trapped in the relief valve assembly to a position that prevents operative contact by the flush valve plunger pin.

RELATED APPLICATION

This is a divisional application of U.S. Ser. No. 09/185,999 filed onNov. 4, 1998 and entitled Apparatus to Prevent Multiple Flushing.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates in general to devices to deter rapidre-engagement of valve opening mechanisms, and more particularly, to animproved delay flush control forming part of a diaphragm flush valveused in a toilet, urinal or similar plumbing fixture.

2. Prior Art

Flush valves, and in particular flush valves used in the construction ofwater closets or urinals, have been used for many years. See, forexample, U.S. Pat. No. 30,462 issued Oct. 23, 1860. However, theforerunner to one of the most popular modem diaphragm flush valvedesigns is disclosed in U.S. Pat. No. 1,714,573 issued May 28, 1929, andcommonly referred to as a diaphragm flush valve. One problem with thediaphragm flush valve is controlling the amount of water used when theplunger handle is continuously being activated. This problem isparticularly acute in prisons and schools where the persons using thetoilet facilities are more likely to misuse the equipment. Principlecauses of this problem are holding the plunger handle down for anextended period of time or continuously engaging the plunger handlewhich unseats the relief valve before a normal flushing cycle has beencompleted. A modified relief valve which addressed the first cause ofthis problem and other problems is disclosed in co-pending U.S. patentapplication Ser. No. 09/152875 entitled “Improved Relief Valve” andfiled on Sep. 14, 1998 by the inventor herein. This invention addressessolutions to the second cause of this problem.

Over the years, improvements have been made to the diaphragm flush valveto provide control of the rapidity of the flushing operation employingelectronic controls or mechanical controls. However, these improvementsinvolve more complex and expensive construction than is desired by theindustry. A second disadvantage of these flush valve designs is thatthey did not permit a simple retrofitting of the flush valve alreadyinstalled, but required a more expensive replacement of an otherwiseworkable flush valve.

OBJECTS AND SUMMARY OF THE INVENTION

Therefore, one object of this invention is to provide an improvedplumbing system utilizing an improved flush valve to control the minimumtime between flushing operations.

Another object of this invention is to provide an improved relief valveused in conjunction with a diaphragm or similar type flush valveprovided with a control means for delaying or retarding the descent ofthe relief valve sleeve member after a flushing operation has begun.

Still another object of this invention is to provide an improveddiaphragm or similar type flush valve containing a relief valve having afloatable sleeve member used in conjunction with a modified vacuumbreaker assembly to control the minimum time between flushingoperations.

A further object of this invention is to provide an improved combinationdiaphragm flush valve and vacuum breaker assembly which is inexpensiveto manufacture and easy to install in a water closet for controlling theminimum time between flushing actions.

A still further object of this invention is to provide a retrofitassembly and a method of installation that can be utilized withconventional diaphragm or similar type flush valves to control theminimum time between flushing operations.

Another object of this invention is to provide an improved method foroperation of a diaphragm flush valve utilized in a plumbing system.

Other objects and advantages of the invention will become apparent fromthe ensuing descriptions of the invention.

The problem of excess water usage caused by repetitive engagement of theplunger handle can be substantially overcome by delaying the reliefvalve sleeve member before it resets in a position to be operativelycontacted by the plunger pin after the relief valve has been reseated.Experience has indicated that increasing this time at least fiveseconds, and more preferably at least ten seconds, will be sufficient todiscourage most persons from unnecessary repetitive engagement of theflush initiating means. In order not to unduly disrupt normal usage, itis preferred that the delay time not exceed sixty seconds.

In one aspect of this invention the time delay can be achieved byconstruction of the flush valve to cause the sleeve member to remainpositioned out of operative contact with the plunger pin for apredetermined period of time before it is repositioned for operativecontact. One such preferred construction is to construct the sleevemember whereby it will float in the water retained in the outletchamber, and to modify the vacuum breaker to drain water trapped in theoutlet chamber of the flush valve when the flush valve diaphragm isreseated.

In another aspect of this invention the time delay can be achieved byconstructing the relief valve whereby the rate of descent is retarded.One such way is to construct the contacting surfaces of the sleevemember and stem to create frictional resistance of a predeterminedamount. Another construction is to fix the sleeve member to the reliefvalve by an elastomeric material have predetermined elasticitycharacteristics.

In still another aspect of this invention the increase in time can beachieved by constructing the relief valve whereby the distance thesleeve member travels after the relief valve has been reseated isgreater than the vertical distance it traveled when operatively engagedby the plunge pin. One such preferred construction is to modify therelief valve stem and sleeve member to have cooperating helical grooveand nib or ridge members that cause the sleeve member to rotate aroundthe stem as it slides vertically. In a preferred aspect of thisembodiment the plunger pin is constructed to force the sleeve memberwhen contacting the sleeve member lower end to vertically move above theplunger pin.

In another embodiment of this invention an improved method for operatinga diaphragm flush valve utilized in a plumbing system is providedwherein the relief valve sleeve member is caused to rise out ofoperative contact position with the plunger pin upon the reseating ofthe flush valve diaphragm and to retain its raised position for apredetermined length of time before returning to its original positionfor operative contact by the flush valve plunger pin.

BRIEF DESCRIPTION OF THE DRAWINGS

The specification and the accompanying drawings show and describepreferred embodiments of this invention, but it is to be understood thatthese embodiments are not intended to be exhaustive nor limiting of theinvention, but on the contrary are given for the purpose of illustrationin order that others skilled in the art may fully understand theinvention and the principles thereof and the manner of applying them inpractical use so that they may modify and adapt the invention in variousforms, each as may be best suited to the conditions of a particular use.

FIG. 1 is a cross-sectional view of a conventional diaphragm flush valveand vacuum breaker assembly positioned for use in a typical watercloset.

FIG. 2 is a three-dimensional view of a vacuum breaker inner linersimilar to that illustrated in FIG. 1, but in accordance with apreferred embodiment of this invention provided with drainage openings.

FIG. 2A is a bottom view of the vacuum breaker of FIG. 2 taken alonglines A—A.

FIG. 2B is a cross-sectional view of the vacuum breaker of taken alonglines B—B of FIG. 2A.

FIG. 2C is a partial cross-sectional view of the vacuum breaker of FIG.2 illustrating the low energy, large surface area lip seal used incertain conventional vacuum breaker inner liners.

FIG. 3 is a cross-sectional view of a preferred embodiment of a reliefvalve sleeve member utilized in a diaphragm flush valve in accordancewith this invention.

FIG. 4 is a cutaway view of another preferred embodiment of a reliefvalve that has been retrofitted in accordance with this invention.

FIG. 5 is a cutaway view of another preferred embodiment of a reliefvalve of this invention whose sleeve member and stem are structured tocause the sleeve member to travel around the stem as it slides along thestem.

FIG. 6 is a cutaway view of another preferred embodiment of a reliefvalve utilizing a compressible member in accordance with this invention.

PREFERRED EMBODIMENTS OF THE INVENTION

As used in this patent, the term “diaphragm flush valve” refers to aflush valve having a fluid inlet chamber, an upper chamber and an outletchamber, wherein the chambers are separated from one another by aflexible diaphragm provided with a by-pass opening connecting the fluidinlet chamber to the upper chamber and with a central opening connectingthe upper and outlet chambers, which central opening is sealable by arelief valve assembly comprising a relief valve having a verticallydisposed stem about which a sleeve member can freely slide apredetermined distance, and a plunger assembly having a flush initiatingmeans which when engaged causes a plunger pin to operatively contact thesleeve member unseating the sealing member and permitting flow of fluidfrom the upper chamber to the lower chamber. Without any intent torestrict the definition of diaphragm flush valves, examples of such aredescribed in U.S. Pat. Nos. 1,714,573, 2,776,812, 3,399,860, 3,556,137,3,656,499, 4,327,891, 5,013,007, 5,026,021, 5,295,655, 5,335,694,5,415,374, and 5,649,686.

Also as used in this patent, the term “vacuum breaker assembly” is usedto include any device utilized to prevent back siphonage from a pollutedfluid source, such as a toilet, back into the non-polluted fluid supplyfeeding into device, which is constructed having an elastomeric innerliner with a receiving end into which the fluid is received by thedevice and a discharge end having a sealable opening through which thefluid must pass before being discharged from the device. Without anyintent to restrict the definition of vacuum breaker assembly, examplesof such are described in U.S. Pat. Nos. 3,334,646, 3,797,515, 5,060,687,5,454,396, and 5,564,460.

A prior art embodiment of a diaphragm flush valve and a vacuum breakerassembly installed in a water closet is illustrated in FIG. 1. The flushvalve includes the brass body 1 provided with an inlet section 2connectable to a pressurized water supply. Section 2 forms inlet chamber23. Body 1 also is provided with an outlet section 3 forming an outletchamber 24 through which water exits the flush valve. Between the inletand outlet sections there is an internal upstanding barrel 4. The upperedge portion of barrel 4 forms the annular main valve seat 5. The mainvalve member comprises a flexible circular rubber diaphragm 6 having abottom valve seating portion 7 and which is clamped to the top end of acylindrical guide member 8, made of a plastic material such asCYCLOLAC7, extending downward within the barrel 4. The diaphragm 6 isprovided with a central opening 9 through which a clamping disc 10extends with a portion 11 threaded into the guide member 8 and therebyclamps the diaphragm 6 tightly between them. A relief valve 12 which maybe made of DELRIN7 plastic material is carried by the clamping disc 10and has a depending operating stem 13 made of brass or other metal. Stem13 extends downward through the diaphragm opening 9 and within the guidemember 8. Sleeve member 14 which telescopes about stem 13 may be made ofDELRIN7 plastic material and is positioned opposite plunger pin 15 whenit rests on the upper surface of shoulders 16 forming a stop member 17at The lower end of stem 13. Plunger pin 15 actively engages sleevemember 14 by its inward movement into the flush valve outlet chamber 24when handle 18 is moved off axis from plunger pin 15. Other flushinitiating means include various electronic sensors or mechanical pushbutton devices, such as described in U.S. Pat. Nos. 2,507,966,2,688,141, 3,066,314, 3,695,288, 3,778,023 and 4,891,864.

The valve body 1 is provided with an external cover 19 and an internalcover 20, the latter preferably being made of an ABS plastic moldedmaterial such as CYCLOLAC7. The external cover 19 is screw threadedaround the top end of the body 1 and provided with a shoulder whichengages the outer peripheral edge of internal cover 20 and presses itdownwardly against the edge 21 of the diaphragm 6 to clamp the diaphragmfirmly around its periphery into position in the valve body.

In the ordinary operation of the flush valve described, the waterpressures in inlet chamber 23 and upper chamber 25 are equalized aboveand below the diaphragm 6 by the flow of water through the small by-passopening 22. Since the pressure area above the diaphragm in upper chamber25 is greater than that in outlet chamber 24 below the diaphragm, thediaphragm is held tightly against main valve seat 5, thereby shuttingoff the water flow between the inlet chamber 23 and outlet chamber 24.The engagement of the plunger pin 15 with sleeve member 14 causes sleevemember 14 to tilt stem 13 from its vertical axis. The tilting of stem 13causes relief valve 12 to also tilt from its seat. With relief valve 12tilted, water can flow from the upper chamber 23 through guide member 8and into the outlet chamber 24 reducing the pressure in upper chamber23. This reduction in pressure now permits water from inlet chamber 23to flex and lift diaphragm 6 from main valve seat 5 permitting water toflow from inlet chamber 23 over the top edge of barrel 4 and into outletchamber 24 to initiate the flushing action. Once plunger pin 15 is nolonger operatively contacting sleeve member 14; i.e., no longer causingsleeve member 14 to tilt or otherwise prevent relief valve 12 fromreseating, relief valve 12 can be reseated. This allows water is fromthe inlet chamber 23 to refill upper chamber 25 until the pressure inupper chamber 25 is again equalized to that in inlet chamber 23. Withthe pressure again equalized, diaphragm 6 reseats preventing furtherflow of water from the inlet chamber 23 to the outlet chamber 24. Theamount of water which flows into the outlet chamber 24 is controlled atleast in part by the time required to achieve pressure equalization inthe inlet and upper chambers resulting from the refilling of upperchamber 25 with water.

Sleeve member 14 depending from stem 13 is constructed to slide up alongstem 13 a sufficient distance to permit sleeve member 14 to rest in anon-operative position above plunger pin 15 if the flush handle 18 isheld unduly long in the operated position. In this position the reliefvalve 12 is no longer tilted and will automatically reseat closingcentral opening 9. In a normal flushing action, flush handle 18 ispushed off axis and then quickly released. In this case, sleeve member14 descends to its original position and relief valve 12 is reseated.Typically, this unseating and reseating of the relief valve 12 takesplace in less than one second, which is sufficient time to permitdiaphragm 6 to be unseated by the water pressure in inlet chamber 23 andfor the desired amount of water to flow first into outlet chamber 24 andthen through vacuum breaker assembly 26 to the water closet bowl (notshown) to complete the flushing action.

To prevent waste water backup into the flush valve and possibly thewater supply lines, government regulations require the use of some typeof structure to prevent this possibility from occurring. One suchstructure is a vacuum breaker assembly. FIG. 1 illustrates one type ofstandard vacuum breaker assembly, such as described in U.S. Pat. No.5,564,460, that is used in a water closet to prevent back siphonage fromthe water closet back into the potable water supply feeding the flushvalve. Vacuum breaker assembly 26 includes an outlet tube 27 havingperipherally spaced air openings 28. A coupling nut 29 is used to attachvacuum breaker assembly 26 to lower section 3. The downstream end ofoutlet tube 27 will be connected to the inlet side of the water closetor urinal (not shown).

Positioned inside of outlet tube 27 is a vacuum breaker inner liner 30which is suitably formed of a rubber like or flexible elastomericmaterial. As is illustrated in FIGS. 2 and 2A-C, the upstream end ofvacuum breaker inner liner 30 includes a flange 31 having a recess 32which supports the outwardly extending flange 33 of an insert orstiffening funnel 34. Stiffening funnel 34 includes a plurality ofopenings 35 for the passage of water. A slip ring 36 is seated on top offlange 31 and forms a portion of the connection between the coupling nut29 and the outlet end of the flush valve. There is a hood 37 which maybe crimped onto the lower end of coupling nut 29 and is used as a shieldfor air openings 28. The hood is spaced from the air openings so thatthey may perform their intended function of admitting air at atmosphericpressure into the interior of the vacuum breaker assembly 26 to preventback siphonage.

Vacuum breaker inner liner 30 includes a body 38 constructed from anelastomer which extends from flange 31. The body is cylindrical andterminates at its lower end in a low energy large surface area lip seal39. There are a plurality of generally equally spaced projections 40 onthe exterior of vacuum breaker inner liner 30, with these projectionsbeing adjacent the downstream end of the sleeve. They are effective toalign, locate and space the exterior wall of body 38 from the interiorof the outlet tube so that air from air openings 28 may enter the spacebeneath the vacuum breaker sleeve 28 to prevent back siphonage.

The lip seal 39 extends from the downstream end of body 38 directlyadjacent the projections 40 and includes a gradually outwardly taperinginner surface 41 and a coaxial or cylindrical outer surface 42, withthese two surfaces terminating in the end 43 of lip seal 39. The outersurface 42 is generally continuous with the outer cylindrical surface ofbody 38. The tapered interior surface 41, at its upper end, is anextension of the interior surface 44 of body 38. The shoulders 45 and 47are formed between lip seal 39 and projections 40 and the interior valvewhich controls the flow of water through the flexible sleeve. The largesurface area lip seal 39, however, is basically a continuation of theinterior and exterior surfaces of body 38.

The interior of vacuum breaker inner liner 30 has three lip sealsindicated at 46, 48 and 50. Each of these lip seals, at the lowerexterior thereof, has ribs 49 which are slightly thicker than otherportions of the lip seals, with the ribs defining between them a slit 51which can open to permit the passage of water through the vacuum breakerassembly 26. Each of the ribs 49, at their upper ends, join with walls52 with the upper end of each of the walls 52 being integral with thebody 38. There are two walls 52 between each adjacent pair of ribs 51.

In normal use the flow of water into the vacuum breaker assembly 26 willpass through the stiffening funnel 34, with water pressure forcing thelip seals 46, 48, and 50 to spread apart, permitting water to flowthrough slits 51 to the water closet, or other plumbing fixtures,connected at the outlet end of the vacuum breaker assembly 26. In theevent there is a negative pressure at the water supply, air will flow inthrough the air openings 28, causing the walls of the vacuum breakerinner liner 30 to collapse upon the support funnel 34, preventing thepassage of water from the downstream water closet into the potable watersupply. The lip seals 46, 48, and 50 assist in preventing such backsiphonage. In the event there is a dramatic increase in back pressurebecause of a water closet restriction as described, the downstream lipseal 39, being thin and directly adjacent the wall of the outlet tube,will rapidly move outwardly against the wall to seal air openings 28.

As the water pressure diminishes in vacuum breaker assembly 26 with thereseating of diaphragm 6, slits 51 close trapping water above slits 51and in outlet chamber 24. However, it has been discovered that if theelastomeric inner liner 30 is provided with at least two openings 53 and54 vertically spaced from one another, and preferably positioned inwalls 52, then water in the outlet chamber 24 can be drained at acontrolled rate. The time required for the water to drain can becontrolled at least in part by the sizing of the two openings. It ispreferred that the cross-sectional area of opening 54 be at least asgreat, and more preferably greater, than the cross-sectional area ofopening 53. If sleeve member 14 is constructed to float in water, thenits descent after the flushing cycle can be delayed by the water fillingoutlet chamber 24.

FIGS. 3 and 4 illustrate alternate embodiments of a sleeve membercapable of floating in water. In FIG. 3 sleeve member 14 comprises anupper section 55 whose outer layer 56 is constructed from materialhaving a density less than water and an inner layer 57 constructed frommaterial, such as a hard plastic, that provides the rigidity needed forsleeve member 14 to retain the integrity of its passageway 58 permittingit to slide along stem 13. The lower section 59, also comprising part ofsleeve member 14, may be constructed from the same or different materialas inner layer 57. If the material used to construct outer layer 56 hasthe necessary rigidity to retain the integrity of passageway 58, thenthe entire sleeve member 14 can be constructed from the same material.Without attempting to limit the materials which can be used to constructouter layer 56, examples would include low density polyurethane orsimilar honeycombed or foamed material, wood, cork, etc.

FIG. 4 illustrates an alternate embodiment especially suited forretrofitting existing sleeve members to permit them to float. In thisembodiment, outer sleeve 60 is constructed of material having a densityless than water and sized to cause sleeve member 14 to be capable offloating, in water. In a more preferred embodiment outer sleeve 60 willfit snugly about sleeve member 14, and still more preferably beconstructed of an elastomer that can be stretched over sleeve member 14and then will constrict to be mechanically fixed to sleeve member 14. Inthis preferred embodiment, a plumbing system employing a standarddiaphragm flush valve and vacuum breaker assembly can be quicklyretrofitted to form one embodiment of this invention. This retrofit canbe accomplished by unscrewing external cover 19 from flush valve body 1and removing the internal cover 20 exposing relief valve assembly 26.Relief valve assembly 26 is lifted out of body 1 and then outer sleeve60 is slipped over sleeve member 14. The modified relief valve assembly26 is reinserted into body 1, and the internal and external coverssecured back into position. To modify inner liner 30 coupling nut 29 isloosened to separate the flush valve from the vacuum breaker assembly26. Inner liner 30 is removed and openings 53 and 54 punched or cut byany standard tool useful for that purpose. Inner lining 30 is reinsertedinto outlet tube 27 and coupling nut 29 is then tightened to reconnectthe flush valve to the vacuum breaker assembly 26.

The function of openings 53 and 54 in inner liner wall is to allow anywater in outlet chamber 24 to drain out through the openings 53 and 54when inner liner slits 51 are closed. In is normal operation plunger pin15 operatively contacts sleeve member 14, water from inlet chamber 23flows through outlet chamber 24 until diaphragm 6 is re-seated. However,as the water pressure is decreased due to the resisting of diaphragm 6,inner wall slits 51 will close trapping the outlet chamber 24. The waterin outlet chamber 24 causes the buoyant sleeve member 14 to float upalong stem 16 into a position above plunger pin 15 where it can nolonger be operatively contacted. Sleeve member 14 will remain out ofposition for operative contact with the plunger pin 15 until the waterlevel in outlet chamber 24 has been lowered sufficiently by the loss ofwater through openings 53 and 54. In this embodiment it is preferredthat guide member 8 be provided with at least one opening 69 (seeFIG. 1) which connects outlet chamber sections 70 and 71 located oneither side of guide member 8. Opening 69 helps prevent the possibilitythat a negative pressure situation might prevent water in sections 70and 71 from draining.

FIGS. 5 and 6 illustrate alternate embodiments of a modified reliefvalve assembly 26 in which sleeve member 14 can be detained for a periodof time from assuming a position permitting the plunger pin 15 fromoperatively engaging sleeve member 14 to initiate a successive flushingcycle. In FIG. 5 the wall surface 61 of stem 13 is provided with ahelical groove 62 extending above stop member 17 and ending at least ata distance from stop member 17 greater than the distance sleeve member14 must travel to avoid operative contact with plunger pin 15 when ithas been activated by plunger handle 18. The wall surface 63 formingsleeve member passageway 58 is provided with one or more nibs 64positioned to extend into groove 62 to cause sleeve member 14 to rotateabout stem 13 as it moves along stem wall surface 61. In an alternateembodiment a helical ridge which loosely mates with groove 62 can beutilized in place of, or in conjunction with, nibs 64. The pitch of thehelix shape of groove 62 can be set to control the distance in whichsleeve member 14 must travel before it again rests on stop member 17.Furthermore, because of the frictional forces between the nibs 64 (orridge) and the walls forming groove 62, the speed at which sleeve member14 descends can also be controlled. In an alternate embodiment nibs 64may extend from stem surface 61 and be sized to fit into a correspondinghelical groove in wall surface 65 forming passageway 58.

The embodiment such as illustrated in FIG. 5 can be used alone or inconjunction with the floating sleeve member described above. If usedalone, it is preferred that plunger pin 15 be constructed having aconical shaped end 72 such as illustrated in FIG. 1. It is furtherpreferred that end 72 operatively contact sleeve member 14 at its lowerend 73. It is further preferred that the inward movement of plunger pin15 be sufficient to cause sleeve member 14 to vertically rise a distancesufficient to position it above plunger pin 15. In this embodimentsleeve member 14 will be required to travel some distance before it isin position for operative contact by plunger pin 15.

In FIG. 6 an elastomer member 66 is connected at its opposite ends 67and 68 to relief valve 12 and sleeve member 14, respectively. Member 66is constructed from materials having elastomeric properties thatincrease the time required for sleeve member 14 to travel before itagain rests on stop member 17 after having been operatively contacted byplunger pin 15. In this embodiment the upward movement of sleeve member14 will compress elastomer member 66. Elastomer member 66 is such thatover time it will rebound to its original non-compressed shape whereonce again sleeve member 14 will be in a position for operative contactby plunger pin 15.

There are of course other alternate embodiments which are obvious fromthe foregoing descriptions of the invention. These and the other obviousalternate embodiments are intended to be included within the scope ofthe invention as defined by the following claims.

What I claim is:
 1. An improved method for operation of a diaphragmflush valve utilized in a plumbing system, the improvement to whichcomprises: (a) causing the relief valve sleeve member to be positionedin non-operative contact with the flush valve plunger pin after therelief valve has been unseated, and (b) retaining said sleeve member ina position of non-operative contact for a predetermined period of timeat least one second greater than the time for said sleeve member totravel to said position under free fall conditions.
 2. An improvedmethod according to claim 1 wherein said predetermined period of time isat least five seconds.
 3. An improved method according to claim 2wherein said predetermined period of time is between about ten secondsand about sixty seconds.
 4. A relief valve for use in a diaphragm flushvalve, the improvement to which comprises the relief valve stem, therelief valve sleeve member, or a combination thereof, constructed torequire the time for said sleeve member to travel from a first positionwherein said sleeve member is out of operative contact with thediaphragm flush valve plunger pin to a second position wherein saidsleeve member can be operatively engaged by said plunger pin to be atleast one second greater than the time for said sleeve member to travelfrom said first position to said second position in free fall.
 5. Arelief valve according to claim 4 for use in a diaphragm flush valvecontained in a fluid flow control plumbing fixture having a vacuumbreaker assembly, wherein the sleeve member of the relief valve isconstructed to have a density that requires the time for said sleevemember to travel from said first position to said second position to beat least one second greater than the time for said sleeve member totravel from said first position to said second position in free fall. 6.In a relief valve according to claim 5 said sleeve member beingconstructed to have a density less than said fluid.
 7. In a relief valveaccording to claim 6 said sleeve member being constructed at least inpart from material having a density less than said fluid.
 8. A reliefvalve according to claim 5, wherein said sleeve member and said stem arepositioned in frictional contact with one another during movement ofsaid sleeve member.
 9. A relief valve according to claim 8, furthercomprising a member having predetermined elastomeric properties attachedto said sleeve member and said seating member or said stem in a mannerto reduce the rate of descent of said sleeve member to a rate less thanthe rate of a free fall descent.
 10. A relief valve according to claim5, further comprising a member having predetermined elastomericproperties attached to said sleeve member and said seating member orsaid stem in a manner to reduce the rate of descent of said sleevemember to a rate less than the rate of a free fall descent.
 11. A reliefvalve according to claim 4, wherein said sleeve member and said stem arepositioned in frictional contact with one another during movement ofsaid sleeve member.
 12. A relief valve according to claim 11, wherein ahelical groove extends along the outer surface of said stem and whereina nib extends outward from the interior wall surface of said sleevemember a sufficient distance and is sized to fit within said groove tocause said sleeve member to revolve around said stem when said sleevemember moves vertically relative to said stem.
 13. A relief valveaccording to claim 12, further comprising a member having predeterminedelastomeric properties attached to said sleeve member and said seatingmember or said stem in a manner to reduce the rate of descent of saidsleeve member to a rate less than the rate of a free fall descent.
 14. Arelief valve according to claim 11, wherein a helical groove extendsalong the interior wall surface of said sleeve and wherein a nib extendsfrom the exterior surface of said stem and is sized to fit within saidgroove to cause said sleeve member to revolve around said stem when saidsleeve member moves vertically relative to said stem.
 15. A relief valveaccording to claim 14, further comprising a member having predeterminedelastomeric properties attached to said sleeve member and said seatingmember or said stem in a manner to reduce the rate of descent of saidsleeve member to a rate less than the rate of a free fall descent.
 16. Arelief valve according to claim 4, further comprising a member havingpredetermined elastomeric properties attached to said sleeve member andsaid seating member or said stem in a manner to reduce the rate ofdescent of said sleeve member to a rate less than the rate of a freefall descent.
 17. In a relief valve for use in a diaphragm flush valvecontained in a fluid flow control plumbing fixture having a vacuumbreaker assembly, wherein the plumbing fixture is constructed to permitat least a portion of any fluid trapped in the outlet chamber of thediaphragm flush valve by the vacuum breaker assembly to drain therefromwhen the relief valve is seated, the improvement to which comprises thesleeve member of the relief valve being constructed to have a densitythat requires the time for said sleeve member to travel from a firstposition wherein said sleeve member is out of operative contact with thediaphragm flush valve plunger pin to a second position wherein saidsleeve member can be operatively engaged by said plunger pin to be atleast one second greater than the time for said sleeve member to travelfrom said first position to said second position in free fall.
 18. In arelief valve according to claim 17 said sleeve member being constructedto have a density less than said fluid.
 19. In a relief valve accordingto claim 18 said sleeve member being constructed at least in part frommaterial having a density less than said fluid.